FASTAREA

Discussion of MicroSurvey CAD related issues and questions.

Moderators: Brian Sloman, Jason Poitras, James Johnston

FASTAREA

Postby rwhatman » Wed Jun 04, 2003 6:53 am

Today I had a problem using FASTAREA program.

The program said the lines did not close. I new better.

It was full of curves and reverse curves. I did not want to take
the time and type it all out.

I changed all the Lines to polylines and joined them all on the fly.

I then used FastAREA program. It then gave me the right area.

It is not listed in the HELP files that this program can close polyline work.

Now I know and everyone who reads this may try it.

This seems to me that the fastArea program could be better if it was changed, so that all line work that is pick to a polyline, joined then exploded after the area is calculated.

The fastArea program would then tell you right where it does not join at the beginning of the 50 picks and not after.

What do you think.
rwhatman
 
Posts: 299
Joined: Sun Nov 10, 2002 6:41 am
Location: Peterborough, Ontario, Canada

Fastarea

Postby Glen Cameron » Thu Jun 05, 2003 9:54 am

From what I understand, the fastarea command uses the PCONTOUR command internally to find the boundary to calculate the area within. This command does create a pline of the boundary but removes it when done so as to not clutter your drawing with things you do not need.

The fastarea command assumes that you have lines overlapping, not just meeting, and with curves it can give a non-closed type error if the simply meet and do not cross.

You can always use the pcontour command yourself to generate the pline around the closed figure - then run the CAD area command and pick the Objects option to allow you to pick the new pline you just created. It does not label the drawing but will give you the area in square units.

Cheers,
Glen W. Cameron, C.E.T.
City of North Bay, Ontario
Glen Cameron
 
Posts: 1395
Joined: Fri Nov 08, 2002 12:18 pm
Location: Corbeil, Ontario, Canada

Postby rwhatman » Thu Jun 05, 2003 10:11 am

PCONTOUR works well, but I the point I was trying to make is that the FASTAREA program will close that very same polyline.

Here I thought I had to explode all the polylines for the program to work.

I tried PCONTOUR on a boundary. Now it made a polyline of the same
boundary.

I then tried the FASTAREA program on both the closed lines and the closed
polylines. I got the same anwser.

Is the FASTAREA program as the CAD AREA command just about the same program only that one prints it on the screen and the other just
displayes it.
rwhatman
 
Posts: 299
Joined: Sun Nov 10, 2002 6:41 am
Location: Peterborough, Ontario, Canada

Fastarea

Postby Glen Cameron » Thu Jun 05, 2003 1:00 pm

The calculations that Fastarea and Area are doing are the same and they will get the same answer. Fastarea does label the area where the Area command does not. Area allows you to pick what it is to use to calc the area in several ways. Fastarea uses the pcontour command and allows you to pick linework only to determin it's boundary to calulate the area.

They are similar but not identical.

Cheers,
Glen W. Cameron, C.E.T.
City of North Bay, Ontario
Glen Cameron
 
Posts: 1395
Joined: Fri Nov 08, 2002 12:18 pm
Location: Corbeil, Ontario, Canada

fast area wishlist

Postby geo » Thu Dec 23, 2004 8:38 am

I've got an issue with fast area too. Is there some way to build in a tollerance of not completely closed polygons? I hate having to go through the hundreds of lines to make sure they are all properly connected. If there was a tollerance setting this would make my life a whole bunch easier. For example, if the polygon doesn't close, and the opening is 0.001m or less, just close it and give me my area.
geo
 

Not as easy as it sounds

Postby Darcy Detlor » Thu Dec 23, 2004 9:11 am

Hi there,

We use internal CAD functions in this program. If your CAD drawing has errors, which gaps are, then the CAD function is not going to work.

Creating a program that corrects for gaps is much more difficult than it may seem because of all the different kinds of entities. How many do you support: Line, Arc, Circle, Polyline, Ellipse, Solid, 3D Face, Polyface Mesh, Rectangle, etc.

We will do some research into it to see whether it is feasible to add this function.
Last edited by Darcy Detlor on Mon Dec 27, 2004 3:51 pm, edited 1 time in total.
Darcy Detlor,
President,
MicroSurvey Software Inc.
[email protected]
User avatar
Darcy Detlor
Site Admin
 
Posts: 205
Joined: Tue Oct 29, 2002 10:14 am
Location: West Kelowna, BC

Postby artb » Mon Dec 27, 2004 7:56 am

2004/12/26

Darcy

In regards to the fast area and what line types you may wish to include in setting a tolerance that would complete the connection of two lines that don't quite meet I will offer the following suggestion.

In my experience requiring areas I see basically 2 linetypes that I would suggest need to be included in that exercise. (lines and arcs). Most of the other linetypes you mention appear to me to relate to volumes rather than areas. Possibly polylines would be a 3rd type. I do know that those 3 line types would look after 95 to 100% of my area situations. That may simplify your problem of creating the program that would deal with the non-connecting lines. I certainly concur with the others on the frustration that is created after you have attempted to close an area only to discover that 2 or morelines couldn't be closed because of fractional miscloses on said lines.

I would think that the tolerance that you would decide to use should be tied to the tolerance that the users sets his/her program up for. In that way the user will be the one to decide how fine a tolerance to use.

Artb
artb
artb
 
Posts: 53
Joined: Thu Oct 28, 2004 8:51 pm
Location: Vernon, B.C.


Return to MicroSurvey CAD

Who is online

Users browsing this forum: No registered users and 2 guests

cron